The present invention is a portable, rapidly erectable and easy to disassemble discone antenna for use in wide band, high frequency ground wave communication.
A study entitled "The Utility of High Frequency Ground Wave In a Distributed Communication System" by one of the inventors James R. Champion was described at a scientific conference Oct. 15, 1990 and was published in Conference Proceedings C. P. 486, The Advisory Group for Aerospace R&D, Neuilly Sur Seine, France, pp. 4-1 to 4-6, 1991. This reference does not describe the particular features of the invention relating to portability, ease of assembly and disassembly but deals mainly with its effectiveness as an antenna. (See paragraph 2.)
A discone antenna is described in "Three New Antenna Types and Their Applications", A. G. Kandoian, Waves and Electrons, 70 W-75 W, Feb, 1946. The benefits of grounding the antenna are mentioned on page 71 W.
Discone antennas are generally described in a scientific article entitled "Designing Discone Antennas", J. J. Nail, Electronics, Vol. 26, pp 167-169, Aug. 1953. The present antenna is constructed according to the basic relationships described in the article and illustrated in FIG. 1.
Neither of these two references discuss the portable feature of the instant invention.
U.S. Pat. No. 3,701,159 entitled "Discone Antenna", is an inverted discone antenna with the ground mat acting as the disc and the cone portion suspended from poles fixed in the ground. It is not useful for high frequency communications, is not portable and cannot be disassembled easily. (See abstract and paragraph bridging columns 1 and 2.)
U.S. Pat. No. 4,143,377 teaches a discone antenna variation wherein two discone antennae are used together, one mounted atop the other. (See abstract and FIG. 1). It is not portable and cannot be disassembled easily.
U.S. Pat. No. 4,918,460 describes a telescopic mast operating in conjunction with reels for winding sets of stays. The masts are useful to support antennas for mobile installations. (See abstract and column 1, paragraph 1.)
U.S. Pat. No. 3,189,906 is a conical antenna wherein the radiating elements serve to brace and support the antenna. This antenna can be adapted for quick assembly. (See column 2, lines 21-26.)
The following three patent references describe portable antennas not of the discone type.
U.S. Pat. No. 3,579,244 describes radiating elements made of flexible thin steel secured to a telescoping mast. Ground elements also made of the thin steel are secured to the mast in a plane perpendicular to the mast. (See abstract.)
Related patents U.S. 4,743,917 and U.S. Pat. No. 4,750,001 teach roll-out antennas wherein the antenna wire is wound onto a reel for transportation and storage. (See abstracts.)